The latest studies on solar geoengineering to tackle climate change are reinforcing the case for a global governance system and further study before deployment, as they show that the approach may have little effect on preventing rainfall changes in the tropics — and may even lead to widespread drought in Africa.
Several geoengineering initiatives plan to tackle climate change by cutting incoming sunlight, through methods such as spreading reflective aerosols in the stratosphere.

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But without also removing carbon dioxide from the atmosphere, such plans would fail to fully mitigate change in rainfall in the tropics, a study published in Nature Geoscience last week

Using a series of climate models, the authors show that even if global temperatures do not rise, the rise in carbon dioxide alone will disrupt rainfall patterns. This is because much future rainfall change in the tropics is expected to happen independently of surface warming; instead it will be driven by a shift in atmospheric vertical motions, induced by a rise in carbon dioxide.